This invention relates to fiberoptic scopes and, in particular, to an intubation scope having an associated integral lightweight portable screen. It is a modification of my previous invention of an intubation scope with camera and screen, U.S. Pat. No. 4,742,819, dated May 10, 1988, which is incorporated herein by reference.
It is frequently necessary in medical procedures to insert an endotracheal tube into the trachea of a patient for the purpose of performing diagnostic tests or for the introduction of some means of ventilation, oxygenation, and/or airway protection. Even in the best situations, intubation is often difficult and can give rise to complications. In many patients, establishment of the airway may be formidable due to morphologic anomalies such as a large tongue, excessive pharygeal or laryngeal soft tissue, or tracheal displacement, as well as physiologic events such as laryngospasm, regurgitation of gastric materials, blood, or foreign bodies. The morphologic anomalies make it difficult to visualize the posterior pharygeal area and larynx. In emergency situations, attempts to intubate such patients are difficult, time consuming, and often meet with failure. Inability to expeditiously intubate the patient and protect the airway can lead to significant hypoxemia. Cases of death have also been related to complications arising from an intubation process, that were caused by inability to quickly and clearly see the larynx and trachea.
Several attempts have been made to provide an intubating scope which facilitates intubation of a patient. U.S. Pat. No. 3,776,222 to Smiddy, entitled "Fiberoptic Intubator and Method of Intubation of the Trachea through the Nasopharynx," discloses an intubator which facilitates intubation through visual means. That invention involves the introduction of an endotracheal tube through the nasal pharynx, facilitated by an internally disposed fiberoptic scope with a single eyepiece at its proximal end. The Smiddy device was devised for use in situations where the patient could assist in placement of the endotracheal tube by swallowing action (when the patient is in an upright position). In an emergency situation, assistance from the patient, even if he is able to maintain an upright posture, is unlikely. Intubation must be quick and accomplished by mechanical means guided only by the attending physician and/or technician.
U.S. Pat. No. 4,086,919 to Bullard discloses a laryngoscope having a single eyepiece attached to the laryngoscope blade and handle. The eyepiece is illuminated by a fiberoptic system. This device also could be improved. If the attending physician looks through the Bullard scope and has to remove his eyes from the eyepiece to make an external assessment of the airway of the patient, a critical lag in time occurs before the physician can refocus on the internal images seen through the eyepiece. The critical lapse of time caused by the process of focusing and refocusing can affect the timely placement of the endotracheal tube and may even cause the physician to misinterpret certain landmarks, hindering the exact placement of the endotracheal tube. Because the eyepiece is attached to the laryngoscope blade and handle, the physician may not be able to see deep enough into the oral pharynx and larynx to visualize the opening to the trachea. Most importantly, the movement of the physician's body and head, down to, and away from, the eyepiece can lead to erroneous placement of the endotracheal tube in a structure other than the patient's airway because of movement of the blade and handle and thus movement of the visual field of the eyepiece.
Fiberoptic scopes designed specifically for anesthesiologists, such as the scope sold by Olympus under the trade designation LF1, may be used for the intubation of a patient. However, they require techniques that are not usually used by attending physicians unless they are specifically skilled in the use of fiberoptic intubating scopes. The intubation of a patient using a fiberoptic scope with an eyepiece such as an LF1 usually calls for more familiarity than is usually attained by many physicians, and in an emergency situation a physician will tend to return to those techniques and instruments with which he or she is most familiar. Thus, although a scope such as the LF1 may be used for intubation, a physician will rarely, if ever, use a fiberoptic scope such as the LF1 in an emergency situation unless he or she is extremely well skilled in its use prior to the emergency situation. Indeed, the use of a device that is not routinely used by a physician, which calls for techniques other than those with which he or she usually uses to perform the intubating process, can lead to disaster by delaying the intubation process or leading to misposition of the endotracheal tube or failure to intubate the patient.
Further, with the LF1 or similar devices, the physician must often use both hands on the scope, requiring an assistant or other extra persons to help position the patient's head and open the mouth. The user must also look through an eyepiece and then remove his or her eye away from the eyepiece to look directly into the airway to adjust the position of the fiberoptic scope. These devices thus have the same disadvantages discussed above with respect to the Bullard scope. Further, the LF1 scope and other bronchoscopes are not easily portable and require time to set up. The set up and intubation are usually time consuming, and are prone to failure in inexperienced hands.
Fiberoptic scopes have been used in association with screens in other areas of medicine as well. Scopes used for arthroscopy with screens set on a large monitor off to one side of the operating room table are just one example. Another example is the use of fiberoptic scopes for the general surgeon in the performance of laparoscopic cholecystectomy. Again, the screen and monitoring images are removed from the direction of the operation. To use such fiberoptic scopes and devices for the intubation of the trachea, especially in patients who present airways that are extremely difficult and formidable to intubate and protect, is not the optimal answer to the emergency intubation situation. If such a scope is inserted through the endotracheal tube to view the patient's airway structures as the endotracheal tube goes out of sight, the physician has to turn his or her head and/or body in a significant manner to view the associated screen. If structures are seen that are not easily identifiable, the physician then has to turn his or her head and body back to the direct viewing of the airway to see just where the endotracheal tube is placed, and make a proper adjustment of the endotracheal tube in the airway in relation to the anatomic structures that are present. Then, as the endotracheal tube goes out of sight again, the physician again has to turn his or her head and body off to the side to again look at the screen. Since the physician does not view the airway directly and indirectly through the screen at the same time, confusion, lack of orientation of the endotracheal tube and its proper position in the airway can result, potentially leading to failure in an emergency intubating process.
The invention disclosed in my prior patent, U.S. Pat. No. 4,742,819, entitled "Intubating Scope with Camera and Screen", comes closer to achieving those conditions which are vital to assuring quick, accurate and easy placement of the endotracheal tube in a patient. Indeed, this invention allows the physician to use those techniques with which he or she is most familiar when intubating the patient, i.e., the use of a laryngoscope blade and endotracheal tube with a stylet. It allows the physician to almost simultaneously see the patient's airway as viewed directly or indirectly through the scope with camera and screen. It further allows the physician to minimally move his or her eyes during this intubating process so that he or she does not have to turn his or her head or body to visualize indirectly the airway, as would be required with a screen that is set off to the side and not close to the direct line of vision of the task at hand. However, at this time the device of my prior invention is relatively expensive and technologically difficult to produce.